SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '144fc1e4b113b6c798af83e28fbe8bd38ddec5e9ba85e65264147ec0eac5b051' 
  AND token = 'rEAFVkw69clkPhZjhOq2ILQeGWJWC47L330Rl8UT1UE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}