SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '900230f3a950f09b087bc628480c20664115e99d7e9c9a77ee0999d1b77c164b' 
  AND token = 'jKnkkDDg4IRQgXmUBsOgQKYKPWn4U/85ttjbmmdU40I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}