SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7c77ccbf54a2f51baced2f04b5fcc206b08b37b5528930a68fb4afec45eb115' 
  AND token = 'rfmw1Iw+xe9CmMCQ7dUKCTcuS6Oyo2MMByfvfq0YwEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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