SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af04a1ec8092e7ac2e71b18d5264977bb995c1ab8a55858797f1dc7c6d77d34e' 
  AND token = '+irQ9UB8nlrWBf6lF2EK50jwGFBXwcV0xpBMIBOX4n8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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